Journal bearing



Q P. 5;. TAYLOR EPA-L. 2,225,136" Y Dec. 17,1 40.

'. JOURNA BEARING l Filed Feb; 14. 19:59 7

NVEN-rbRS V PHIHPBTMOR *3? "Patented Dec.17,1940 a I UNlTED STATES PATENT OFFICE miiffii'lm Philip B. Taylor, Upper Montclair, and Wilton'G. Lundquist, Glen Mk, N. J., assignors to Wright Aeronautical Corporation, a corporation of New York Application February 14,1939, Serial No. 256,280 14 Claims. (Cl.1846) This invention concerns the cooling of bear- Fig. 1 is a longitudinal section through a radial ings, relating-particularly to the crankpin bearengine crankshaft incorporating the cooling pro- 'ings of crankshafts used in radial cylinder invisions of the invention; g

ternal combustion engines, 4 Fig. 2 is a longitudinal section of the crankpln 5 It so happens that in radial cylinder engines portion of a shaft showing an alternative ar- 6 thepredominantloadlng on the crankpin iour-, rangement, and nal under all normal operating conditions is on Fig. 3 is a section on the line 33 of Fig. 2. a the inside of the journal -that is, that sector or In Fig. 1, weillustrate a more or less convensegment of the journal closest to the crankshaft tional radial engine crankshaft comprising a 0' center line. This is due to the fact that the cenforward shaft element In, a crankcheekv l2 and 1 ter of gravity of the connecting rod system ina crankpin It integral therewith, the cranlrpinv cluding the pistons ls approximatelycoincidenbeing bored out as at is to lighten the assembly tal' with the crankpin center and aicordingly, and also to provide an oil containing cavity; The the centrifugal force of the system acts radially shaft member I0 is also hollow for lightness. To outward upon the crankpin despite the explosion the rear end of the crankpin M a rear cheek i8 loads imposed thereon by any engine cylinder is clamped by a bolt 20, the cheek having an which may be in its power cycle. The centrifintegral shaft journal 22 embraced by 'a bearing ugal force of the system is greater than any of 24 carried in the conventional manner in the the individual piston and rod power impulses or supporting crankcase structure, The shaft l0 inertia effects. Thus, the maximum bearing likewise is carried in a bearing 26 supported in I! pressureoccurs upon the-inside of the crankpin the crankcase, not shown. 1 I I and the greatest amount of frictional heat is In the rear cheek l8 an extension shaft 28 is concentrated in this inner zone. The convensplined as at 30, this extension shaft having a I tional lubricating system for this type of enjournal 32 engaging anoil transfer bearing 34 1 85 ,gine utilizes a hollow crankshaft for conducting fed from an oil pump 36. The extension shaft lubricating oil to the various bearings including is hollow as indicated'and conducts oil from the the crankpin bearing and this oil serves the transfer bearing to a.c0ndliit 38 comprised by added function of removing heat from the crankradial drillings in the crankcheek l8 inthe rear pin journal, this being virtually the only means end of the crankpin i4 and in a. plug form- ,30 of cooling the journal since little or no heat ing a closure for the crankpin bore l8. Said plug radiating surface is provided therefor. 0n the carries an integral cylindrical extension 40 closed other hand, bearing friction heat developed in at its forward end, projecting into the bore ii in the connecting rod itself is dissipated with comspaced relation to the walls thereof, said extenparatively little difficulty since this member nor- ,sion 40 having holes 42 on that wall thereof mally has a considerable surface area and is which faces the axis of the shaft assembly. Oil moving at high speed within the engine crankmay pass into the hollow of the extension 40, case. through the holes 42 to impinge upon that wall It is an object of this invention to provide imof the bore 16 which is closest to the crankshaft provements in cooling of crankpin journals, 8. axis. Thence, theoil fills the bore l6 and from further object being to provide means by which the bore oil is led through a tube 44 to the 40 the bearing coolant is so directed as to impinge connecting rod bearing, the connecting rod being first upon the hottest parts of the Journal whereindicated at 46. Oil also passes through a conby the temperature of the whole Journal ismainduit 4B in the crankcheek I2 and in the shaft tained at a substantially uniform level. A furportion Ill for lubricating other parts of the .46 ther object is to provide means for cooling hollow' engine. v v shafting, an associated object to so organize the As pointed out toward the beginning of the cooling system that the hottest parts of the shaft specification, the innermost part of the crankreceive the cooling medium first as it enters the pin l4, indicated at, A, is virtually continuously journal zone, whereby the temperature of the loaded under a high unit bearingpressure, from system is maintained substantially uniform and which local frictional heat is developed, other I wherebythe heat is removed from the hottest parts-of the. pin sustaining little or no bearing shaft portions as it is generated therein. load. Since the lubricating oil is directed against Further objects will become apparent in readthat 'part of the crankpin bore wall closest to the ing the annexed detailed description in connecloaded portion A, heat is properly removed tion with the drawing,-in which, therefrom by the impingement .of cooling oil did thereon, resulting in a more uniform tempera-'- ture throughout the periphery of the crankpin.

In Fig. 2, we show the crankpin I 4' integral with the shaft l0 and the cheek l2, said pin l4 being bored as above described and having formed integrally with the pin, and within the bore 16, a plurality of cooling fins 52 which are segmental in form, the segments occupying only a zone in the bore 16' which is closest to the crankpin axis. The crankpin plug 39 with its extension 40 is similar to that first described. The finned crankpin interior permits of the di'ssipation of a greater amount of heat to the cooling oil directed thereagainst. This finned crankpin arrangement may be used in crankshaft systems where the inner side of the crankpin journal shows evidence of excessive temperatures.

Although the provisions of this invention are particularly shown in connection with crankshafts for radial cylinder engines, use may be made of the principles of the invention in any kind of shaft system wherein cooling of journals is required or wherein certain portions of the journals run hotter than others. For instance, any journal having a bearing load applied predominantly to one side thereof is a suitable subject for the application for the principles of the invention.

While we have described our invention in detail in its present preferred embodiment, it will be obvious to those skilled in the art, after understanding our invention, that various changes and modifications may be made therein without departing from the spirit or scope thereof. We aim in the appended claims to cover all such modifications and changes.

We claim as our invention:

1. In an engine crankshaft having a hollow crankpin, means borne by the pin tending to load the pin predominantly and continuously on one side thereof, whereby said loaded side tends to become hotter than other partsof the pin, means for introducing cooling lubricant within the pin hollow, and means directing the introduced lubricant first against that part of the interior wall of the pin closest to said loaded side and thence through the crankpin to the crankpin bearing for lubrication thereof.

2. In an engine crankshaft having a hollow crankpin, means borne by the pin tending to load the pin predominantly and continuously on one side thereof, whereby said loaded side tends to become hotter than other parts of the pin, means for introducing cooling lubricant within the pin hollow, and means directing the introduced lubricant first against that part of the interior wall of the pin closest to said loaded side, said interior wall part having heat radiating fins formed thereon and thence through the crankpin to the crankpin bearing for lubrication thereof.

3. In an engine crankshaft having a hollow c'rankpin, means borne thereon tending to load the pin predominantly and continuously in one sector thereof, cooling fins within said hollow on that part of the pin closest to said loaded sector, and means for directing cooling lubricant first over and upon said fins and thence to the crankpin journal for lubrication thereof.

4. In an engine crankshaft having a hollow crankpin, means borne thereon tending to load the pin predominantly and continuously in one sector thereof, cooling fins within said hollow on that part of the pin closest to said loadedsector, and means for directing cooling lubricant first over and upon said fins, said means comprising a lubricant conduit within said hollow having lubricant outlet openings directing lubricant toward said fins and said crankpin having a through'opening for lubricant passage from the hollow to the crankpin bearing. I

5. In an engine crankshaft having a hollow crankpin, means thereon tending to load the pin predominantly and continuously in one sector thereof, and means for directing cooling lubricant first upon the interior wall of the pin closest to said loaded sector and thence to the crankpin bearing.

6. In an engine crankshaft having a hollow crankpin, means thereon tending to load the pin predominantly and continuously in one sector thereof, and means for directing cooling lubricant first upon the interior wall of the pin closest to said loaded sector, said means comprising a lubricant conduit within said hollow having lubricant openings directed toward said interior wall, and means to conduct lubricant from the hollow to the crankpin bearing.

7. In a hollow Journal and bearing assembly wherein the load therebetween predominates on a certain sector of the journal thereby causing a temperature rise thereat disproportionate to the temperature rise at other parts of the journal, means directing cooling lubricant predominantly toward the part of the interior journal wall closest .to said predominantly loaded sector, and means conducting lubricant from the journal hollow to the journal bearing.

8. In a hollow journal and bearing assembly wherein the load therebetween predominates on a certain sector of the journal, thereby causing a temperature rise thereat disproportionate to the temperature rise at other parts of the journal, means directing cooling lubricant predominantly toward the part of the interior Journal wall closest to said predominantly loaded sector, said means including a cooling lubricant conduit within the Journal having nozzles for lubricant outlet facing toward said interior journal wall part, and means conducting lubricant from the journal hollow to the journal bearing.

9. In a hollow journal and bearing assembly wherein the load therebetween predominates on a certain sector of the journal, thereby causing a temperature rise thereat disproportionate to the temperature rise at other parts of the journal, means directing cooling lubricant predominantly toward the part of the interior journal wall closest to said predominantly loaded sector, cooling fins formed upon said interior journal wall part, and means conducting lubricant from the journal hollow to the Journal bearing.

10. In an engine crankshaft comprising a hollow crankpin embraced by a bearing and a main hollow journal joined to the crankpin by a cheek, means to feed oil to said hollow Journal, said cheek having an oil conducting drilling connecting with the journal hollow, a tube fitted within the crankpin in clearance relation with the interior wall thereof, means to lead oil from the cheek drilling to the interior of the tube, said tube having a series of holes facing those parts of the crankpin which tend to run hottest whereby oil within the tube is directed through said holes against the hottest crankpln portions, and duct means through the crankpin conducting oil from the hollow thereof to the crankpin bearing.

11. In an engine crankshaft comprising a hollow crankpin embraced by a bearing and a main hollow journal joined to the crankpin by a cheek, means to feed oil to said hollow Journal, said cheek having an oil conducting drilling connecting with the journal hollow,'a tube fitted within the crankpin in clearance relation with the interior wall thereof, means to lead oil from the cheek drilling to the interior of the tube, said tube having a series of holes facing those parts of the crankpin which tend to run hottest whereby oil within the tube is directed through said holes against the hottest crankpin portions, and duct means through the crankpin conducting oil from the hollow thereof to the crankpin bearing, said duct means being on the outer part of the crankpin and the tube holes opening toward the inner part of the crankpin.

12. In a hollow shaft rotatable in a bearing the shaft being loaded continuously through only one sector thereof whereby the shaft tends to become heated at the loaded sector to a greater extent than at the balance of the shaft, means to feed lubricant to the shaft hollow, means carried by the shaft and lying within the shaft hollow for directing entering oil to the wall adjacent the shaft for cooling same, beto other parts ,of the shaft loaded sector of the fore said oil passes hollow, and a d ct through the shaft wall for conducting lubricant from the shaft hollow to the bearing.

13. Inan engine crankshaft having a hollow crankpin fed with cooling lubricant, means loading the pin predominantly and continuously in one sector thereof, means for conducting lubricant from the pin hollow to the journal bearing at the unloaded side thereof, and means to guide the entering lubricant in its flow to said-conductagainst and along that part of the inof the crankpin closest to said loaded ing means terior wall sector. 7

14,. In a hollow journal and bearing assembly wherein the load therebetween predominates on a certain sector of the journal. means to conduct lubricant into the Journal hollow, means 

